A conventional device for dewatering fibrous material is disclosed in WO99/66122 in FIG. 1. In this device, a fibrous stock suspension is applied via a headbox to a wire conveyor, and a fibrous web is formed in the process. Following this, the fibrous web is dewatered by a first press, what is known as the “lump breaker”. This press has a nip which is formed by a wire roll and by a couch roll. Here, the couch roll is wrapped around by a felt.
The problem with this press is that the felt is overloaded at high production speeds and pressing of the web occurs.